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Re: cygwin 1.3.17-1 gethostbyname() leak


Pierre,

Corinna's earlier post indicated that using this pointer collided with
Cygwin's fork/exec mechanism...
	Igor

On Tue, 10 Dec 2002, Pierre A. Humblet wrote:

> On Wed, Dec 11, 2002 at 06:12:21AM +1100, Noel Gordon wrote:
>
> > If it is true that cygwin uses gethostbyname() from wsock32.dll, and
> > returns the wsock32.dll hostent* result to the application, then it
> > is perhaps unwise to free() it. Following your tip, we find from ...
> >
>
> In net.cc cygwin takes the result from the MS GetHostByName and copies
> it to its own calloc'ed structure.
> Not sure why, given that the MS function already returns a pointer to
> a per thread structure, as indicated below.
>
> Pierre
>
> > http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winsock/winsock/gethostby
> > name_2.asp
> >
> >   Remarks
> >
> >   The gethostbyname function returns a pointer to a hostent structure - a
> >   structure allocated by Windows Sockets. The hostent structure contains
> >   the results of a successful search for the host specified in the name
> >   parameter [of gethostbyname()].
> >
> >   The application must never attempt to modify this structure or to free
> >   any of its components. Furthermore, only one copy of this structure is
> >   allocated per thread, so the application should copy any information it
> >   needs before issuing any other Windows Sockets function calls.
> >

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